Abstract The impact of two-step inoculation of indigenous strains and their synergistic effect in the scaling-up of petroleum hydrocarbons biodegradation from a mineral-based medium (MBM) to a two-phase composting process were investigated. After isolating the strains KA3 and KA4 from heavy oily sludge (HOS), their emulsification index (E24), bacterial adhesion to hydrocarbon (BATH), and oil degradation efficiency were evaluated in the MBM. Then, they were inoculated twice into the composting bioreactors lasted for the primary 8 weeks as the first phase (FP) and subsequent 8 weeks as the second phase (SP). The results indicated that the consortium of the two strains degraded 16-61% of crude oil (1-5% concentration) in the MBM. In the composting reactors, removals of 20 g kg−1 initial concentration of total petroleum hydrocarbons (TPH) were found to be 63.95, 61.00, and 89.35% for the strains KA3, KA4, and their consortium, respectively. The computed biodegradation constants indicated the synergistic effect of the two strains and the effectiveness of the second-step inoculation. The study demonstrated the successful scaling-up of HOS biodegradation from MBM to the two-phase composting process through two-step inoculation of the isolated strains.

中文翻译：

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利用本地分离菌的协同作用通过两步接种堆肥工艺生物降解重油污泥

摘要 研究了两步接种本地菌株的影响及其在石油烃生物降解从矿物基介质 (MBM) 到两相堆肥过程的放大过程中的协同效应。从重油污泥 (HOS) 中分离菌株 KA3 和 KA4 后，在 MBM 中评估了它们的乳化指数 (E24)、细菌对碳氢化合物的粘附 (BATH) 和油降解效率。然后，将它们两次接种到堆肥生物反应器中，持续 8 周作为第一阶段 (FP)，随后的 8 周作为第二阶段 (SP)。结果表明，两种菌株的聚生体降解肉骨粉中 16-61% 的原油（1-5% 浓度）。在堆肥反应器中，对于菌株 KA3、KA4 及其聚生体，发现 20 g kg-1 初始总石油烃 (TPH) 浓度的去除率分别为 63.95、61.00 和 89.35%。计算出的生物降解常数表明两种菌株的协同作用和第二步接种的有效性。该研究表明，通过对分离菌株进行两步接种，HOS 生物降解从 MBM 成功扩大到两相堆肥过程。